log exit code and pid on verbose logging

Is useful for debugging on daemon.

dvc/cli/__init__.py

@@ -173,10 +173,10 @@ def main(argv=None):  # noqa: C901, PLR0912, PLR0915
     args = None
 
     outer_log_level = logger.level
+    level = None
     try:
         args = parse_args(argv)
 
-        level = None
         if args.quiet:
             level = logging.CRITICAL
         elif args.verbose == 1:
@@ -235,11 +235,15 @@ def main(argv=None):  # noqa: C901, PLR0912, PLR0915
         ret = _log_exceptions(exc) or 255
 
     try:
+        import os
+
         from dvc import analytics
 
         if analytics.is_enabled():
             analytics.collect_and_send_report(args, ret)
 
+        logger.trace("pid %s exiting with %s", os.getpid(), ret)  # type: ignore[attr-defined]
+
         return ret
     finally:
         logger.setLevel(outer_log_level)